Derivatives and Hedge Accounting - Derivatives not Designated as Hedging Instruments (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	$ (75)	$ (129)	$ (59)	$ (204)
Net investment income - Fortitude Re funds withheld assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	0	(1)	$ 0	$ (1)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Net Investment Income	Net Investment Income
Excluding Fortitude Re Funds Withheld Assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	(22)	(98)	$ (20)	$ (126)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Investments	Investments
Fortitude Re funds withheld assets
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	(53)	(30)	$ (39)	$ (77)
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Investments	Investments
Interest rate contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	(2)	(4)	$ (1)	$ (5)
Foreign exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	(22)	(111)	(17)	(144)
Embedded derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Total	$ (51)	$ (14)	$ (41)	$ (55)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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